In the art of woodworking, various devices or tools may be used to join, connect or otherwise hold together wood parts for assembly thereof, such as by gluing or the like. Examples of such devices include, without being limited to, vises, bar clamps, pipe clamps, C-clamps, and several other types of clamps. Among these different varieties of clamps, bar clamps and pipe clamps, hereinafter collectively referred to as bar clamps, are common clamps for edge-gluing of wood parts to produce workpieces such as laminated wooden panels used, for example, in furniture or cabinet construction. Bar clamps can also be employed for joining together other materials such as plastics or metal parts. Depending on the intended application, bar clamps may be used to hold wood parts together, parallelly or perpendicularly to one another, at various stages of the assembly process such as, for example, before and after gluing, and before securing fasteners.
Conventional bar clamps generally include a movable member (e.g. a slide jaw) and a fixed member (e.g. a fixed jaw), between which may be disposed wood parts to be glued, joined or otherwise held together. The movable member may be configured to move or slide along a length of the bar while the fixed member may be provided with an adjusting handle (e.g. an adjusting screw) for applying pressure to the wood parts. In a typical use of bar clamps, the movable member is moved until it is separated from the fixed member by a distance that is slightly wider than the total width of the wooden components to be clamped. The bar clamp is then tightened by turning the adjusting screw, which results in a compressive force being imposed on the wood parts. In turn, this ensures that the wood parts are properly aligned and joined while being glued or otherwise fastened together.
While existing bar clamps may be suitable for some applications, there remain several drawbacks associated therewith. More specifically, a general issue with conventional bar clamps is that they generate compressive forces that are strictly longitudinal, that is, oriented along the length of the bar clamps. In other words, as clamping forces are applied lengthwise between the movable member and the fixed member, conventional bar clamps are often restricted to generating one-dimensional clamping forces only.
As a result, when, for example, narrow pieces of wood are edge-glued together in order to form a wider laminated wooden panel, the compressive clamping force applied to the wood pieces by the bar clamp remains in the plane of the resulting wooden panel. In other words, no compressive or maintaining force is imposed perpendicularly to the plane of the laminated wooden panel, that is, across its thickness. This may be problematic in circumstances where applying compressive forces in more than one direction with respect to the components to be joined together by the bar clamp is desirable. These circumstances may arise, for example, when one wishes to form a multilayered panel, stabilize and hold steady pieces to be joined, or reduce deformations that may occur during the drying process of the adhesives used to join wood pieces. In such cases, existing bar clamps cannot be used alone and other specialized clamping devices need to be provided. These specialized clamping devices may be cumbersome to use and expensive to purchase. Moreover, installing, adjusting and tightening each of these additional clamping tools add lengthy steps to the overall process of fabricating a complete workpiece.
Another drawback associated with existing bar clamps is that the range of possible thicknesses for the final workpiece is limited by the size of the adjusting handle and that of the throat of the bar clamp. As a result, several different bar clamps must be purchased in order to fabricate workpieces of different thicknesses, thereby incurring additional costs. Moreover, existing bar clamps are typically not well suited for joining materials thicker than about 2½ inches.
In light of the above, a need exists in the art for a bar clamp and a bar clamp assembly capable of imposing compressive forces to a workpiece along more than one dimension thereof, while also possibly alleviating at least some of the drawbacks of the prior art.